Electric resistor furnace



Patented Apr. 28, 1925. i

UNITED ASTATES 1,535,547 PATENT oFFicE.

THOMAS A. REID, F WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRIC RESISTOR FURNACE.

'Application led August 28, 1922. Serial No. 584,620.

To all whom t may concern:

Be it known that I, THOMAS A. REID, -a citizen-of the United States, and a resident of lVilkinsburgLin the county of Allegheny and State of Pennsylvania, have invented a new and useful lImprovement in Electric Resistor Furnaces, of which the following is a specification.

My invention relates to furnaces and,

particularly, to electrically-heated resistance furnaces.

The object of my invention is to provide a relatively simple resistor mounting for an electrically-heated resistor furnace.

In practising my invention, I provide a plurality of refractory heat-insulating walls enclosing a. furnace chamber and supporting a plurality of spaced-apart. sets of refractory members, of substantially T-shape,

projecting into the furnace chamber. The refractory members of T-shape are spaced apart laterally, and relatively thin refractory plates, having grooves in their inner surfaces, are held by the outer ends of the members of T-shape. A relatively heavy resistor member, preformed to com rise a pluralityof straight and substantial y parallel-extending end-connected convolutions, is held bythe grooved plates whereby the convolutions extend substantially parallel to the furnace walls and closely adjacent thereto In the single sheet of drawin s,

Figure 1 is a view, in vertica lateral section, of an electrically-heated pit-type furnace embodying my invention;

Fig. 2 is a fragmentary view, ,partly in side elevation and partly in longitu inal section, of an electrical-resistance furnace embodying my invention;

Fig. 3 is a top plan View of a refractory supporting member;

FiO'. 4 is a view, in side elevation, of the mem er shown in Fig. 3;

Figs. 5 and 6 are top plan and side eleva.- tional views, respectively, of a modified form of supporting member;

Fi s. 7 and 8 are top plany and side elevationa views, respectively, of a still further modification of a supporting member; and

Figs. 9 and 10 are top plan and side elevational views, respectively, of lgrooved resistor-supporting members employed in the furnace embod ing my invention'.

An electric urnace, designated generally walls are suitably spaced apart to constitute or enclose a furnace chamber 15 of any suitable or desired contour and dimensions. A mule lining for the furnace chamber 15 may comprise a plurality of spaced-apart and vertically-extending hollow tile members 16 which alternate with a. plurality of refractory bricks or blocks 17 which, in turn, are spaced apart vertically by refractory supporting members 18, of substantially T-shape, the T-end of which extends into the furnace chamber.

l Means for supporting a charge to be placed within the furnace chamber 15 may comprise a plurality of suitabl'erefractory members 19 embedded in the bottom linings of the furnace structure.

The furnace structure 11 has an open top which is closed, during'the operation of the furnace, by a pluralit" of cover members 21 85 and 22,. The lower-e ges of the cover members 21 and 22 rest in masses 23 and 24 of sand which, in turn, are located in members 25 and 26, of substantially channel form in lateral section, located adjacent the outer and the inner edges of the walls of the furnace structure at the top thereof. This construction is more particularly disclosed and claimed in a copending application by G. H. Cole, Serial No. 580,400, filed Aug. 8, 1922, and assigned to the Westinghouse Electric & Manufacturing Company, (Case No. 9590). Y

The members 18, of substantially T-shape, are more particularly illustrated in Figs. -3 100 and 4 of the drawing and, as there shown, are provided with two openings 27 extending laterally therethrough immediately adjacent the end of T-shape. As hereinbefore stated, the members 18 are located in spaced- 105 apart relation in a vertical direction, and relatively thin refractory plates 28, each having a plurality of grooves 29 extending laterally thereof on one surface, are supported by the respective members 18 imme- 110 diately adjacent the wall of. the furnace. Instead of grooves and ridges, a plurality of integral projections alined laterally of the plate'may bev employed, as illustrated in Figs. 9 and 10. The 'plates 28 are so held that the grooved surface is immediately ad jacent to, and faces, the wall of the furnace.

Means for preventinglateral movement of the plates 28 relatively to the support-mg members 18 may comprise meta-l rods 31, of L-shape, which are droppedv into the opening 27, the width of the plate 28 being such as to extend substantially between the two members 31 to be held thereby against lateral movement relatively tothe supporting members 18'.

A resistor member 32 is located in the grooves 29 of the resistor-supporting plates 28 and extends between and vbeyond these resistor-supporting members and comprises a plurality of straight and substantially parallel-extending. end-connected convolutions of a relatively heavy resistor bar which is self-supporting between the resistor-supporting plates 28. No means for' making electrical connections with ends of the resistor member 32 is shown, as any suitable or desired construction usually employed in the art may be used. While I have illustrated the heating elements as located in the side arid end walls only, the same general .constructionv may be employed in the roof of a furnace.'

Figs. 5 and 6 illustrate a modified form of refractory-supporting members of T- .shape -having only a single opening 27 ex'- tending laterally therethrough. The relatively thin resistor-supporting plates 28 em'- ployed with this member of T-shape may be provided with a longitudinally-extending groove 33 adjacent to one end thereof within which a portion'of the key member 31 may be located, theother portion of the locking or key member 31 being located within the opening 27.

Figs. 7 and4 8 illustrate a still further modification of the refractory-supporting members of T-shape, in which a groove 34; extends laterally of the member 18 immediately adjacent` to the overhanging flanges of the member. The groove 34' extends from one edge v'to within a short distance of the other edge of the member, and an opening 27 is located adjacent that edge of the member 18 to which the groove 34 extends. The edges of the plates 28 are located in the grooves 3i, and a key or locking member 31 is placed in the opening 27 to prevent lateral movement of the plates 28 in that direction, the shoulder adjacent the other edge of the member 18 preventing lateral movement of the plates in that direction.

In assembling the parts embodied in the furnace structure, the supporting members of T-shape are located in proper spacedapart relation, substantially as illustrated 1n the drawing, and, in mounting the heating element, the preformed resistor member 32 is hel-d against the wall of the furnace, after which the individual plates 28 may be slipped into place back of the overhanging flanges of the members of T-shape adjacent the walls, and facing the same so as to be held thereby( The locking keys 31-may then be laced in position, thus completing the insta lation ofthe resistor member.

Various modifications may be made in the device embodying my invention without departing from the spirit and scope thereof, and I desire that only such limitations shall be placed thereon as are imposed by the prior art or are specifically set forth in the appended claims.

I cla-im as my invention:

1. An electric-resistance furnace comprising a plurality of refractory walls enclosing a furnace chamber, a plurality of longitudinally spaced-apart sets of relatively narrow and laterally spaced-apart refractory supporting members supported by said refractory walls and projecting into said chamber, relatively thin and narrow resissoy tor-supporting plates each having a plu.

rality of laterally extending grooves inv one face thereof, a relatively heavy unyielding preformed resistor member supported `at spaced vintervals by said grooved plates in co-operation with the refractory walls, and means for maintaining said groovedresistor-supporting members in operative en- `tory walls and pro]ecting into said ,chamoer, relatively thin and narrow resistor-supporting plates each having a plurality of laterally extending grooves in one face thereof, said grooved supporting members being removable from said supporting members in a plane parallel to the surface of the furnace wall, and means for maintaining said grooved resistor-supporting members in operative engagement with said refractory supporting members.

3. In an electric-resistance furnace, in combination, a plurality of refractory walls enclosing a furnace chamber, a plurality of longitudinally spaced-apart rows of` relatively narrow refractory `supports. of substantially T-shape supported by one of said walls and having the T-end extending into said furnace chamber, said supports being spaced apart vertically in said rows, relatively thm and narrow resistor-supporting iso' plates extending between, and supported by, jacent the T-end of said refractory supsaid refractory supports of T-shlpe, each ports for preventing lateral movement of 1 lplate having a plurality of grooves in the said grooved plates.

face that operatively engages a furnace wall, In testimony whereof, I have hereunto and a relatively heavy unyielding preformed Subscribed my name thls 5th day of August resistor member having spaced portions 1922 thereof resting in said grooves to be supported by said plates, and means located ad- THOMAS A. REID. 

